das Stichwort
keyword
A keyword or search term used to search for information in an index, a database, or on the internet.
Geben Sie das Stichwort „Goethe“ in die Suchmaske der Bibliothek ein.
Enter the keyword “Goethe” in the library search form.

keyword / cue
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keyword
A keyword or search term used to search for information in an index, a database, or on the internet.
Geben Sie das Stichwort „Goethe“ in die Suchmaske der Bibliothek ein.
Enter the keyword “Goethe” in the library search form.

The word is made up of “Stich” (cue, hint) and “Wort” (word). Here, “Stich” can be understood as a hint or signal. So a “Stichwort” (keyword/cue) is a word that serves as a signal or as a central point for something.
Er hat mir das richtige Stichwort gegeben, und dann fiel mir alles wieder ein.
He gave me the right cue, and then everything came back to me.
In the meaning “kurze Notiz” (short note), the plural “die Stichworte” (keywords/notes) is almost always used. People rarely speak of just one single “Stichwort” (keyword/note), but rather of a collection of notes.
Ich habe mir für das Meeting nur ein paar Stichworte gemacht.
I only made a few notes for the meeting.
In the context of theater or agreed signals, fixed expressions are common: “jemandem ein Stichwort geben” (to give someone a cue), “auf das Stichwort warten” (to wait for the cue), or “sein Stichwort verpassen” (to miss one’s cue).
Der Techniker wartete auf das Stichwort des Regisseurs, um die Musik zu starten.
The technician waited for the director’s cue to start the music.
When “Stichwort” (keyword/search term) means a search term, it is often combined with the verbs “eingeben” (to enter) or “suchen” (to search). The phrase “unter dem Stichwort ... finden” (to find under the keyword ...) is also typical.
Unter dem Stichwort „Datenschutz“ finden Sie alle relevanten Dokumente.
Under the keyword “data protection,” you will find all relevant documents.
sign / symbol
'das Zeichen' and 'das Stichwort' can both prompt another person to do or say something. 'Zeichen' is very general here and can be a gesture, a look, a sound, or a signal. 'Stichwort' is more specific: it is often a particular word or a short hint that has been agreed on beforehand or briefly names a topic. Learners may confuse the words because a 'Stichwort' sometimes works like a 'Zeichen'. When you mean a general signal, 'Zeichen' fits better. When a word triggers the next step or briefly summarizes a topic, 'Stichwort' is more natural.

Als das Stichwort „Pause“ fiel, räumten alle ihre Unterlagen weg.
When the cue 'break' was given, everyone put away their documents.
Vor dem Termin gab mir Anna ein Zeichen, damit ich mit dem Gespräch anfangen konnte.
Before the appointment, Anna gave me a sign so I could start the conversation.